Top 100 Wind Energy Vocabulary Words | Denmark

A wind turbine turns, but the interesting questions start after you notice the movement. What is turning inside? How much electricity was produced over the day? Why can two machines with the same rated power deliver different amounts of energy? This guide teaches 100 wind energy vocabulary words in English so you can follow the explanation and ask a useful next question.

Denmark is a strong setting for this learning because of its wind-energy research and engineering. DTU Wind and Energy Systems connects turbine design, measurement and wider energy systems. Its work offers a practical way to learn that a turbine is both a machine and part of a network of people, data, electricity and decisions.

Begin with parts and processes, then practise reading a simple output record. Each entry has a meaning, a natural collocation and an original example. “Top 100” is a curated educational list, not a measured frequency ranking. The terms are mainly general English technical vocabulary contextualised through Denmark, and the numerical exercises are fictional rather than reports from an actual wind farm.

Would you write MW or MWh?

Try this statement: “The turbine produced 10 MW yesterday.” It may confuse a power level with energy generated over a day. Ask what was measured: instantaneous output, average power, rated capacity or total energy? If you cannot separate them, begin with groups 5–6 before interpreting a performance chart.

Now explain the difference between rotating the blades about their own axes and turning the nacelle to face a changing wind direction. Both involve movement, but pitch and yaw name different relationships. If all parts of the machine become “the fan”, begin with groups 1–4.

Students can label an institutional turbine diagram. Parents can ask which unit belongs to a daily total. Teachers can change the observation period and check whether the learner revises the calculation. The purpose is not to rush into advanced engineering, but to give an ordinary explanation a sound first set of connections.

Contents: find a useful word group

Airflow, forces, turbine parts, control and electricity: 1–50

1–10: Describe the wind as a changing resource

11–20: Connect airflow with force and motion

21–30: Name the turbine parts

31–40: Describe control and measurement

41–50: Keep electrical quantities distinct

Output, testing, operation, system choices and communication: 51–100

51–60: Read an output record honestly

61–70: Follow testing from a sensor to a conclusion

71–80: Describe operation over time

81–90: Place the turbine within an electricity system

91–100: Discuss choices without turning the vocabulary into a slogan

Worked example · Practice · Speaking and writing · Questions · Sources

Wind speed, direction and variability are different measurements. A useful record includes where, when and how observations were made.

No.	Word or term	Meaning and usage	Natural collocation	Original example
1	wind speed	The rate at which air moves past a point.	measured wind speed	The chart gives wind speed at a stated height and time.
2	wind direction	The direction from which the wind comes, under the stated convention.	prevailing wind direction	The learner checks the wind direction before interpreting the turbine's orientation.
3	gust	A brief increase in wind speed relative to surrounding conditions.	wind gust	The record distinguishes a gust from the period's average speed.
4	turbulence	Irregular fluctuations and mixing within airflow.	atmospheric turbulence	The study discusses turbulence separately from a steadily increasing wind speed.
5	wind shear	A change in wind velocity with position, often height.	vertical wind shear	The diagram shows wind shear between two measurement heights.
6	roughness	Surface characteristics that influence airflow near the ground.	surface roughness	The model names roughness without treating every field as identical.
7	wake	A downstream region of altered flow behind an object such as a turbine.	turbine wake	The layout study considers a wake affecting another turbine.
8	wind resource	The wind conditions available for possible energy production at a site.	site wind resource	The report assesses the wind resource rather than judging one windy afternoon.
9	onshore	Located on land, in the wind-energy context used here.	onshore wind farm	The comparison identifies an onshore project without assuming one standard landscape.
10	offshore	Located at sea, in the wind-energy context used here.	offshore wind energy	The learner distinguishes offshore location from the turbine's rated power.

Offshore is a location, not a guarantee of constant output. An average speed does not reveal the whole distribution of speeds, turbulence or operational constraints. Keep the variables separate before making a performance claim.

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These broad engineering terms help explain why a rotor turns. They are not a complete aerodynamic model.

No.	Word or term	Meaning and usage	Natural collocation	Original example
11	aerodynamics	The study of air motion and its interaction with bodies.	turbine aerodynamics	The lesson connects aerodynamics with the blade rather than the generator alone.
12	airfoil	A shaped cross-section designed to produce useful aerodynamic forces.	blade airfoil	The diagram labels an airfoil section at one point along the blade.
13	lift	An aerodynamic force component perpendicular to the relative airflow.	aerodynamic lift	The drawing uses lift to explain a component of the blade's force.
14	drag	An aerodynamic force component aligned with the relative airflow.	aerodynamic drag	The learner distinguishes drag from the useful torque about the rotor axis.
15	angle of attack	The angle between an airfoil's reference line and the relative incoming airflow.	blade angle of attack	The educator distinguishes angle of attack from the blade's pitch setting.
16	torque	The turning effect of a force about an axis.	rotor torque	The explanation follows torque from the rotor into the drive system.
17	rotation	Turning around an axis.	rotor rotation	The learner describes rotation without confusing it with the nacelle's yaw movement.
18	rotational speed	The rate at which a rotating component turns.	rotor rotational speed	The record gives rotational speed with its unit.
19	load	A force, moment or other demand acting on a component or structure.	structural load	The test measures a load instead of assuming output reveals every mechanical demand.
20	fatigue	Progressive damage associated with repeated loading cycles.	fatigue testing	The study discusses fatigue without calling every stopped turbine damaged.

Pitch angle and angle of attack are related but not identical. Relative airflow also depends on motion and conditions. A short definition should help you read a diagram without pretending that one angle alone explains all blade behaviour.

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The machine’s visible outline hides different mechanical jobs. Some designs omit a gearbox, so a component list is not a promise about every turbine.

No.	Word or term	Meaning and usage	Natural collocation	Original example
21	rotor	The rotating assembly, commonly including blades and hub in a wind turbine.	turbine rotor	The learner labels the rotor rather than calling the entire machine a blade.
22	blade	An aerodynamic component that interacts with wind to drive the rotor.	rotor blade	The diagram follows one blade from root to tip.
23	hub	The central component connecting the blades to the rotor shaft arrangement.	rotor hub	The hub joins the blade roots within the labelled assembly.
24	nacelle	The housing containing major turbine equipment above the tower.	turbine nacelle	The nacelle houses equipment rather than functioning as a storage battery.
25	tower	The supporting structure raising the rotor and nacelle above the ground or platform.	turbine tower	The drawing separates the tower from its foundation.
26	shaft	A rotating mechanical component transmitting motion and torque.	drive shaft	The explanation follows the shaft between labelled drive-system components.
27	gearbox	A mechanism that changes rotational speed and torque through gears.	turbine gearbox	The record identifies a gearbox rather than assuming all turbines have one.
28	generator	A machine converting mechanical energy into electrical energy.	electrical generator	The generator converts the rotor's mechanical input into electrical output.
29	bearing	A component supporting relative motion while carrying loads.	main bearing	The condition report identifies a bearing as one monitored component.
30	foundation	The structure transferring a turbine's loads to supporting ground or seabed.	turbine foundation	The diagram distinguishes the foundation from the tower above it.

The U.S. Department of Energy’s turbine explanation includes geared and direct-drive arrangements. Use the diagram matching the design you are studying. More technical vocabulary should make the machine clearer, not force a missing gearbox into it.

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Control words name how a turbine responds to conditions. The vocabulary is for reading explanations, not operating equipment.

No.	Word or term	Meaning and usage	Natural collocation	Original example
31	pitch	The orientation of a blade about its lengthwise axis, or adjustment of that orientation.	blade pitch	The controller adjusts pitch as part of the turbine's operating strategy.
32	yaw	Rotation of the nacelle and rotor orientation about the tower's vertical axis.	yaw control	The diagram uses yaw to explain alignment with changing wind direction.
33	brake	A device or mechanism used to slow or stop motion.	mechanical brake	The source identifies a brake without suggesting visitors should operate it.
34	controller	A system that processes information and directs operation.	turbine controller	The controller uses inputs rather than judging conditions from appearance.
35	sensor	A device detecting or measuring a physical quantity.	measurement sensor	The study checks the sensor before trusting the recorded values.
36	anemometer	An instrument measuring wind speed.	cup anemometer	The diagram labels the anemometer separately from the wind-direction instrument.
37	wind vane	An instrument indicating wind direction.	nacelle wind vane	The wind vane supplies direction information in the illustrated arrangement.
38	lidar	A light-based remote measurement technology used for quantities such as wind velocity.	wind lidar	DTU's measurement work includes lidar applications and calibration.
39	cut-in speed	The wind speed at which a turbine begins producing useful electrical output under specified conditions.	turbine cut-in speed	The learner checks the stated cut-in speed rather than inventing one for all models.
40	cut-out speed	The wind-speed condition at which a turbine is shut down under its control strategy.	specified cut-out speed	The record explains cut-out speed as an operating limit, not a daily average.

A turbine may stop for several reasons, including maintenance, control limits or system instructions. A still photograph cannot establish the cause. Use the operation record before writing that the machine is broken or the wind has vanished.

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Units are part of the meaning. A clear explanation names the quantity before reporting its value.

No.	Word or term	Meaning and usage	Natural collocation	Original example
41	power	The rate of energy transfer or conversion.	electrical power	The chart reports power at a particular moment rather than a daily total.
42	energy	A quantity transferred, converted or used over a process or period.	generated energy	The report gives energy for the complete observation period.
43	watt	The SI unit of power, equal to one joule per second.	power in watts	The learner uses watt for a rate rather than an accumulated quantity.
44	kilowatt	One thousand watts, a unit of power.	kilowatt rating	The fictional device has a kilowatt rating stated in its specification.
45	megawatt	One million watts, a unit of power.	megawatt capacity	The nameplate gives megawatt capacity without promising continuous full output.
46	kilowatt-hour	An energy unit equal to one kilowatt sustained for one hour.	kilowatt-hour reading	The meter's kilowatt-hour total covers a stated interval.
47	megawatt-hour	An energy unit equal to one megawatt sustained for one hour.	megawatt-hour output	The exercise reports megawatt-hour output rather than megawatts for a daily total.
48	voltage	Electrical potential difference between two points.	operating voltage	The diagram identifies voltage without turning it into a measure of stored energy.
49	current	The rate of flow of electric charge.	electrical current	The learner distinguishes current from the potential difference driving a circuit.
50	frequency	The number of repeating cycles per unit time; specify the electrical context.	grid frequency	The report distinguishes grid frequency from the rotor's rotational speed.

A megawatt-hour is not “megawatts per hour”. The first is energy; the second would describe a change in power over time. Small wording differences can change an entire numerical claim.

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Performance terms require a time period, a system boundary and appropriate definitions. They answer different questions.

No.	Word or term	Meaning and usage	Natural collocation	Original example
51	rated power	The specified power output under stated design or operating conditions.	turbine rated power	The learner reads rated power as a specification rather than a constant observation.
52	installed capacity	The combined rated generating power of the equipment included in a stated system.	installed wind capacity	The report states which turbines are included in installed capacity.
53	capacity factor	Actual energy output divided by rated-power output over the same period.	annual capacity factor	The calculation uses capacity factor without calling it conversion efficiency.
54	efficiency	Useful output divided by relevant input under a stated definition.	conversion efficiency	The learner identifies the input before discussing efficiency.
55	power curve	A relationship between turbine power output and wind speed under defined conditions.	measured power curve	The study compares a measured power curve with its stated reference.
56	average	A summary value calculated under a specified method.	average power	The learner states that the average covers the complete day.
57	peak	The highest recorded or specified value in a stated context.	peak output	The peak occurs briefly and does not describe the entire period.
58	variability	The extent or pattern of change in a quantity.	output variability	The chart shows variability that a single average would conceal.
59	availability	The fraction of time or opportunity equipment is able to operate under a stated definition.	technical availability	The report defines availability before comparing two machines.
60	curtailment	A deliberate reduction of output below what could otherwise be generated.	wind curtailment	The record identifies curtailment rather than attributing every low output to weak wind.

Capacity factor is not the percentage of wind captured, the proportion of time a rotor spins or the share of national electricity supplied. Define the numerator and denominator. Then the number has a useful meaning rather than an impressive-looking percent sign.

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DTU’s testing work makes measurement vocabulary especially relevant. A result needs more than a graph with a smooth line.

No.	Word or term	Meaning and usage	Natural collocation	Original example
61	calibration	Establishing the relationship between an instrument's indications and reference values.	sensor calibration	The report records calibration before using the sensor's output in a comparison.
62	measurement	An observation expressed as a quantity through a defined method.	wind measurement	The learner gives the height and interval for the wind measurement.
63	uncertainty	The limits of precision or knowledge associated with a result.	measurement uncertainty	The chart includes uncertainty instead of pretending every estimate is exact.
64	baseline	A defined reference used for comparison.	performance baseline	The study names the baseline before describing an improvement.
65	prototype	A development version used to explore or test a design.	turbine prototype	The prototype provides test evidence, not proof of a completed commercial project.
66	test rig	Equipment arranged to test a component or system.	blade test rig	The test rig applies a defined investigation rather than reproducing every field condition.
67	simulation	A model-based representation used to investigate a system's behaviour.	flow simulation	The learner distinguishes simulation output from a direct field measurement.
68	validation	Checking a model or result against appropriate independent evidence.	model validation	The methods section explains validation using a separate dataset.
69	dataset	An organised collection of observations or records.	measurement dataset	The dataset has a documented period and method.
70	repeatability	The closeness of repeated results under the same specified conditions.	test repeatability	The report discusses repeatability without claiming that all sites behave identically.

DTU describes power-curve work, load measurement and lidar calibration among its activities. These are distinct investigations. A successful power test does not automatically answer every question about lifetime, costs or environmental effects.

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A wind project includes work before and after electricity begins flowing. These terms help read a timeline without confusing a plan with a completed stage.

No.	Word or term	Meaning and usage	Natural collocation	Original example
71	commissioning	Checks and activities preparing equipment or a project for service.	turbine commissioning	The timeline places commissioning before the reported operational period.
72	operation	The functioning or running of equipment or a system.	normal operation	The record separates normal operation from the scheduled maintenance window.
73	maintenance	Work intended to keep equipment functioning or restore its condition.	planned maintenance	The report identifies maintenance rather than calling all stopped hours a fault.
74	inspection	A structured examination of condition or compliance.	blade inspection	The source describes inspection without claiming every defect is visible from the ground.
75	condition monitoring	Following equipment condition through observations or measurements.	bearing condition monitoring	The study links condition monitoring with a particular component.
76	repair	Work to restore function or condition after a problem.	component repair	The record distinguishes repair from a complete turbine replacement.
77	downtime	A period when equipment is not operating under a stated definition.	maintenance downtime	The learner includes downtime within the full reporting period.
78	reliability	The ability to perform a required function under specified conditions over time.	turbine reliability	The report defines reliability rather than inferring it from one quiet day.
79	repowering	Replacing or substantially renewing generating equipment at an existing project.	wind-farm repowering	The proposal describes repowering without treating it as already completed.
80	decommissioning	The process of taking equipment or a project out of service.	project decommissioning	The plan includes decommissioning as a later responsibility.

A component test, a monitoring alert and a confirmed fault are different records. Keep the stage visible in your English: proposed, tested, commissioned and operating do not mean the same thing.

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A useful account follows electricity beyond the machine. Network capability and time matter alongside generation.

No.	Word or term	Meaning and usage	Natural collocation	Original example
81	grid	The connected system used to transmit and distribute electricity.	electricity grid	The diagram connects the wind farm to the grid through other equipment.
82	transmission	The bulk movement of electricity across a network, commonly at higher voltages.	electricity transmission	The source distinguishes transmission from local distribution.
83	substation	A network installation for functions such as switching and changing voltage.	offshore substation	The learner identifies the substation separately from the generating turbines.
84	transformer	A device used to change alternating voltage levels through electromagnetic action.	power transformer	The transformer changes voltage rather than creating additional energy.
85	interconnector	A connection linking separate electricity networks or systems.	electricity interconnector	The diagram shows an interconnector without assuming a fixed flow direction.
86	demand	The power or energy required by users over a stated basis.	electricity demand	The learner specifies whether demand is an instantaneous level or a period total.
87	balancing	Keeping supply and demand matched through appropriate system actions.	system balancing	The explanation places balancing at system level rather than one turbine alone.
88	storage	Holding energy for later use through a specified technology.	energy storage	The proposal names storage capacity and power capability as separate quantities.
89	forecast	An estimate of future conditions or output based on available information.	wind-power forecast	The forecast remains an estimate rather than a completed generation record.
90	integration	Connecting a resource or component into a functioning wider system.	wind integration	The essay explains integration through networks, operation and information.

A battery stores energy; it does not create the energy it later supplies. A network connection also does not guarantee unlimited transfer at every moment. Technical and operational limits belong in the explanation when the source identifies them.

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These terms help write about projects, evidence and trade-offs. None is a substitute for a current project assessment.

No.	Word or term	Meaning and usage	Natural collocation	Original example
91	renewable	Replenished through ongoing natural processes on the relevant human timescale.	renewable energy	The learner uses renewable without claiming that equipment requires no materials.
92	life cycle	The connected stages from material supply and manufacture through use and end of service.	turbine life cycle	The comparison includes the life cycle rather than operation alone.
93	emissions	Releases of substances to the environment, specified by substance and boundary.	life-cycle emissions	The report states which emissions and stages its estimate includes.
94	recycling	Processing recovered material into material for further use.	blade recycling	The study names recycling without assuming every component follows the same route.
95	assessment	A structured examination using stated evidence and criteria.	environmental assessment	The learner identifies the scope of the assessment before summarising its result.
96	consultation	A process of seeking views or information from relevant participants.	community consultation	The record describes consultation without claiming unanimous agreement.
97	trade-off	A choice involving benefits alongside costs or constraints.	planning trade-off	The paragraph explains a trade-off rather than presenting one word as a verdict.
98	mitigation	Action intended to reduce a harmful effect or risk.	impact mitigation	The proposal identifies mitigation measures that still need evaluation.
99	monitoring	Repeated observation to follow a condition or effect over time.	environmental monitoring	The plan distinguishes monitoring from an already demonstrated outcome.
100	evidence	Information supporting or challenging a claim.	project evidence	The summary keeps evidence separate from a confident forecast.

Renewable does not mean consequence-free, and identifying a trade-off does not settle the decision by itself. A useful paragraph states the question, the evidence and the criteria being used, with enough detail for a reader to follow the reasoning.

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Worked example: the same rated power, different energy totals

Imagine two fictional turbines, A and B, each rated at 2 MW. Over a complete 24-hour day, A generates 24 MWh and B generates 12 MWh. These numbers are invented for learning and are not Danish operational data.

If either turbine had produced continuously at rated power, its reference energy would be 2 MW multiplied by 24 hours: 48 MWh. A’s capacity factor for that day is 24 divided by 48, or 50 per cent. B’s is 12 divided by 48, or 25 per cent. Both calculations use the same rated power and reporting duration.

A’s average power is 24 MWh divided by 24 hours, or 1 MW. B’s average power is 0.5 MW. The nameplate rating has not changed, but the measured energy and average output differ. “A has twice B’s rated power” would be false in this exercise.

Can we conclude that B is poorly designed? No. The record does not give wind conditions, maintenance, curtailment or other relevant information. It supports a statement about the observed day, not a general verdict about design quality or lifetime performance.

Now change the question to an operational request. Ask for the period’s wind measurements and status records before comparing causes. A clear message might say: “The turbines have the same rating, but B generated less energy during the stated day. Please provide the wind and operating records needed to investigate the difference.” The message is useful because it asks for the missing link.

Denmark makes the measurement story visible

DTU Wind and Energy Systems describes research across turbine design and broader energy systems. Its Test and Measurements section identifies work such as power curves, loads and lidar calibration, including activities at Danish test centres. These are specific examples of a research setting, not claims that every turbine or project in Denmark has the same performance.

The institution’s combination of technicians, engineers and researchers is useful for vocabulary learning. Sensor, calibration, dataset and uncertainty belong beside blade, rotor and generator. A machine’s behaviour becomes understandable through the methods and people producing evidence about it.

Use a DTU research page to choose one question: what is measured, how is the instrument checked, or what does the test represent? Then write a short explanation using the source’s scope. Do not turn a research ambition into a completed national outcome.

Denmark’s wider learning guide connects geography, coasts, heritage and living craft. That variety is a helpful reminder that a country’s engineering strength is one entry point, not its entire identity. You can connect a coastal map with an offshore engineering question while keeping the two sources and their purposes distinct.

An original data conversation: repair the unit before the conclusion

Learner: “This turbine made 20 megawatts yesterday.” Partner: “Is that a power level or the day’s energy?” Learner: “The table says 20 MWh.” Partner: “Then what should the sentence say?” Learner: “It generated 20 megawatt-hours during the day.” This is an invented teaching exchange.

The revision is not cosmetic. It changes the quantity being reported. A fluent sentence with the wrong unit can be less informative than a hesitant but accurate one. Check the variable, unit and period before polishing style.

Try a second exchange in which a partner confuses pitch with yaw or capacity factor with efficiency. Ask them to point to the relevant part of a diagram or calculation. Returning to a concrete relationship is often faster than adding another memorised sentence.

Practice: choose the quantity before choosing the word

Answers and explanations

A. Average power is 18 MWh divided by 12 hours: 1.5 MW. Reference energy is 3 MW times 12 hours: 36 MWh. Capacity factor is 18/36, or 50 per cent.

B. No. Capacity factor compares actual energy with continuous rated-power energy over the same period. Conversion efficiency concerns a specified input and useful output.

C. Pitch concerns a blade’s orientation about its lengthwise axis. Yaw concerns the nacelle and rotor orientation around the tower’s vertical axis.

D. No. Those are possible explanations that need appropriate operating evidence. Stillness alone does not identify the cause.

E. For example: “Wind is a renewable energy resource, while equipment manufacture, operation and end-of-service stages still involve materials and effects.”

F. A strong request names the common period and asks for relevant wind measurements and operating status, without presuming the cause of the difference.

Turn the glossary into an explanation someone can check

Start with rotor, blade, nacelle, generator, pitch, yaw, power, energy, rated power and capacity factor. Retrieve the words through a diagram and a small numerical record. Then explain three contrasts aloud without reading the definitions.

Return later with a different reporting period. A learner who understands the relationship should change the reference energy when the hours change. This is retrieval connected with reasoning, not a trick designed to catch someone out.

Parents can ask which unit belongs to a daily total. Teachers can give two sources that measure different quantities and ask for a careful comparison. Keep an early response and a later independent response so improved precision is visible.

The language transfers into engineering, energy journalism, data analysis and public discussion. Formal project decisions need current technical evidence and criteria. A vocabulary guide gives you a better entrance into the conversation, not a ready-made verdict on every project.

Frequently asked questions

Are power and energy interchangeable?

No. Power is a rate; energy is an amount. MW measures power and MWh measures energy.

Does every wind turbine have a gearbox?

No. Direct-drive designs are another arrangement. Use the diagram and specification of the actual design.

Is offshore wind constant?

No. Offshore describes location. Output still depends on conditions, equipment and system operation.

Is capacity factor the same as availability?

No. Capacity factor compares energy with a rated-power reference, while availability describes readiness or ability to operate under a stated definition.

Are the calculations actual Danish project results?

No. They are original fictional examples for learning. Danish research sources provide context, not those invented measurements.

Sources and the scope of this guide

Sources checked on 15 October 2026. All turbine figures and dialogues are invented teaching examples. Technical definitions are original learner explanations. No current national output share, price, project forecast or operating instruction is supplied.

Cambridge Dictionary: power — the physics sense, distinct from broader everyday uses.

DTU Wind and Energy Systems: Research — the Danish research setting and its range of investigations.

DTU: Test and Measurements — power curves, loads, sensors and lidar calibration as distinct activities.

U.S. Department of Energy: Explore a Wind Turbine — parts, control systems and geared versus direct-drive arrangements.

U.S. Department of Energy: Small Wind Guidebook — general technical and measurement terminology, not Danish planning rules.

U.S. Energy Information Administration: Capacity factor — the actual-energy to full-power-reference relationship.

U.S. Department of Energy: Wind Vision glossary — power and energy units in a dated technical reference.

Next: explain one output record with the right units

Write the rated power, reporting duration and generated energy on three separate lines. Explain what each establishes, then calculate only what those values support. End with the information you would need to explain a difference in performance.

The published English Tuition | Denmark develops purposeful explanations using the learner’s actual task. The Denmark learning guide widens country study through geography, history and craft rather than treating one industry as the whole country.

Use the Master English Vocabulary Guide for retrieval and transfer into independent speaking and writing. Formal school requirements remain specific to the course and qualification being followed.